Improvement in machine for filing saws



dal tant Patenti GEORGE W, RATHBUN, OF NORTH PROVIDENCE, RHODE ISLAND,

Latas Patent No. 87,289, daad Fama/ry 23, 1869.

To all whom, it may concern Bc it known that I, GEORGE W. RATHBUN, ofNorth Providence, in the county of Providence, and State of RhodeIsland, have invented a new and useful Improvement in Apparatus forSharpening Saws; and I do hereby declare that the followingspecification, taken in connection with the drawings making a part ofthe same, is a full, clear, and exact description thereof.

Figure l is a view, in perspective, of the apparatus.

Figure 2 is a view of the file-holder.

My invention is intended to provide a means for sharpening a saw, sothat all the teeth can be filed to the same pitch and angle of out,without involving any more skill than is required to adjust and thenfollow the guidance of the apparatus.

A A are jaws of a suitable vise, or clamp, for holdf ing firmly thesaw-plate.

These jaws are attached to the arms B B, of convenient length, when theapparatus is attached to a bench, to bring the saw-plate to the heightrequired for the workman.

These arms are, at the point where they are pivoted together, soconnected by a clutch-face, a, and clampscrcw l), to the face of acorresponding clutch, a, upon a standard-block, G, that they can beadjusted to stand at any preferred angle.

The standard-block, too, is held to the bench b v a clamp-nut passingthrough its foot-piece, to allow of further adjustments in the positionof the apparatus to the operator.'

"From the inner arm B projects a brace, D, which is pivoted thereto atc, and lheld by a clamp-nut.

To the opposite end of this brace is secured firmly a guide-bar orplate, E, the top surface of which is planed smooth, and its edges areparallel with each other.

Upon this guide-bar the following devices are `mounted A carriage orframe, F, is fitted to the guide-bar by means of keepers, so that it canbe slid along the bar, and it can be retained at any point thereon by.means of' a spring friction-finger, G, worked by the lever-d.

From the top of the carriage F a stud-pin, e, projects, which pin,extending also downward beneath the top plate of the carriage, furnishesa fulcrum for the friction-finger, before mentioned.

Upon this same pin, also, asa fulcrum, is placed an indicatingfinger-bar, H.

This bar, whose` front end is turned up, as seen at m, is limited as tothe extent of the arc through which it can be moved by means of a stop,h, projecting from the side of the lever. I, which lever is pivoted alsoto the stud-pin e, and, by means of a clamp-nut, i, passing through aslotted quadrant-plate, J, which terminates the shorter arm of thefinger-bar H, can be secured at different angles with such bar H, andconsequently limit, according to such angle, the arc through which theplate or bar H can be moved.

'lhe device for holding the file consists of a straightedged bar, K,furnished with a longitudinal channel, 7.', into which channel it isintended that the end of' the stud-pin e, projecting above the top platej', shal enter.

A shank, L, of a length equal to that of the le to be used, andfurnished with a collar, l, forms apart of the holder, as seen at fig.2.

A temper-screw, inserted in the collar, and made to operate against theferrule of the handle of the'flle, holds the file in position, the pointof the file resting in 'a hole in the end plate of the channelled bar K,as shown.

Let it be supposed, now, that the saw-plate has been clamped in the jawsA A', and the apparatus adjusted with reference to the intended angle ofcut and pitch to be given to the tooth, as follows:

The guide-bar E is raised or lowered to the desired elevation, and thecarriage F is moved along the bar, until the le, placed in the firstnotch of the saw-plate, with the straight-edged bar K, resting on thetop of the carriage, (the stud-pin c being entered into the channel 15,)stands at the desired angle with the plate. The tooth is then carefullysharpened.

WVhen this has been done, the file-holder is then allowed to rest in theposition in which it will then be, and the finger-bar H is brought sothat the side of its bent-up end m will bear lightly against the edgeofthe straight-edged bar K of the holder.

The lever I is now moved so that its projecting stop h will bear againstthe side of the carriage-frame. It is their clamped fast to thequadrant-plate upon the end of H.

It is now evident that the file can be shifted to the next, or any othertooth, and tle carriage being moved along until the side of theturned-up end of the bar H touches the side ofthe straightedged bar K ofthe holder, and at the same time the stop [L on the leverI is brought upagainst the carriage-frame, such tooth will, upon working the file, bedressed identically with the first, or pattern tooth, without anyspecial care being given to the work.

After the true position of the -ile has been indicated by the finger-barH, it need not, during the sharpening of the tooth, continue to restagainst the edge of the bar K of the tile-holder, but may be moved awaytherefrom, until the angle of the next tooth requires to be indicated.

It is also obvious, without` further explanation, that all the positionsin which the file and saw-plate must be placed, in order to sharpen asaw for any variety of cut, can be accommodated by this apparatus.

What I claim as my invention, and desire to secure by Letters Patent,is-

An apparatus for uniformly dressing the teeth ot a saw, which consistsof holding-jaws, or clamps, A', for the saw-plate, a carriage, F,sliding on a .suitable guide, E, attendant indicatory bar, H, andadjustable stop on, in combination with a suitable le-holder,substantially in the manner herein shown and described.

I also claim the file-holder, consisting ofthe straight edged barK,shank L, and collar l, in combination, substautially as described, forthe purposes specified.

GEORGE W. RATHBUN.

Witnesses:

JOHN D. THnnsToN, GHAs. W. GREENE.

